The present invention relates to a transmission, in particular for electric hand-held power tools, and preferably for angle grinders.
With angle grinders, a manually operated locking device (spindle lock) is usually provided on the transmission housing. By pressing and holding a button, it is ensured that the spindle does not rotate when the grinding disk is installed or removed. This is attained by the fact that, when the locking device is actuated, a bolt engages in a recess in the driven gear, thereby preventing it from rotating. Since the driven gear is fixedly connected with the spindle, the spindle is also prevented from rotating. Manual locking devices for electric hand-held power tools are known, e.g., from U.S. Pat. No. 4,448,098 and U.S. Pat. No. 3,802,518.
Automatic locking devices are also known with drills, drill/drivers, and rotary hammers. The known locking devices automatically block the spindle when torque is transferred from the spindle to the drive. When torque is transferred from the drive to the spindle, the spindle is automatically released. Electric hand-held power tools of this type with automatic locking devices are described in DE 100 03 773 A1 and U.S. Pat. No. 5,016,501.
From publication DE 102 59 519 A1 it is known to dampen vibrations in the drive train of electric hand-held power tools using resilient damping elements located between the driven gear and the spindle.